JPS5913210B2 - Method for manufacturing film-type collagen artificial skin - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing artificial skin using a collagen material as a raw material, and more specifically, a method for producing artificial skin using a collagen material as a raw material. The present invention relates to a method for producing a film-type artificial skin made of collagen, which is formed by extruding it into a shape, solidifying it, or pouring it directly onto a support, drying it, and then crosslinking it using an aldehyde or by irradiating it with ultraviolet rays.

Extensive traumatic skin defects are very common in the surgical and orthopedic field.

Treatments for this have already been put into practical use, such as ointments and lipanol gauze, and recently, sophranol gauze, fibrin membranes, etc. have come into use. However, each of these has advantages and disadvantages, and is not necessarily satisfactory. The collagen artificial skin produced by the method of the present invention has been found to have significantly better therapeutic effects than conventional treatment methods when used for wounds, burns, and wounds after harvesting skin grafts in animals including humans. Ta. The inventors of the present invention focused their attention on producing artificial skin made of collagen using collagen, which is a biological protein that is a constituent of living organisms.

Collagen is originally a major protein that constitutes the bones and skin of animals, and is effective for cell growth when used as a base for cell culture, and is also effective against pseudoendometrial formation. In recent years, collagen has been widely used in medical applications such as dialysis membranes, artificial corneas, artificial vitreous bodies, sutures, artificial blood vessels, and hemostatic sponges, and is attracting attention as a unique biomaterial with many advantages.It is also used as an industrial raw material. Can be manufactured in large quantities. The collagen fiber dispersion used in the present invention can be produced as follows.

Animal rawhide, such as cowhide, is washed and put through a fretting machine to remove the meat side, and then dehaired with enzymes or lime at 28°C.
Concentration of lime solution (CaCOH)2 at the following temperature: 0.5-3
0%) for 1 to 30 days. In some cases, lime treatment may be omitted. After cleaning, neutralize the alkali,
Furthermore, an aqueous solution of an organic or inorganic acid, such as lactic acid 0.5~
Acid swelling is performed by immersing in a 5% aqueous solution at 20° C. or lower for 1 to 10 days. Mechanically micronize or defibrate the acid-swollen skin,
A homogeneous pasty substance is obtained. This paste-like material is further diluted with dilute acid to uniformly disperse it to obtain a collagen fiber dispersion having a collagen concentration of 0.2-6%. Alternatively, the skin after hair removal is washed, the neutral skin after neutralizing the alkali is mechanically finely divided and uniformly dispersed, and then collagen is added to an organic or inorganic acid aqueous solution, such as a 0.5 to 5% lactic acid aqueous solution. Concentration 0.2-6
% and uniformly dispersed to obtain a collagen fiber dispersion. On the other hand, the collagen aqueous solution used in the present invention can be produced by treating animal rawhide, particularly purified cowhide, by a known method (for example, as described in Japanese Patent Publication No. 37-14426, No. 46-15033). In the present invention, the collagen aqueous solution prepared as described above is used alone, or the collagen aqueous solution is prepared based on the dry collagen of the dispersion, and the dry collagen weight of the solution is 20-100%.
Mix and disperse so that the collagen concentration is 0.2'-6
% mixed solution is produced and this is used as the stock solution for molding. These stock solutions are poured into a tubular or planar shape through an annular nozzle or a slit nozzle using a concentrated salt solution (for example, 15% or more of common salt, 1% or more of ammonium sulfate).
5% or more) to form a film by discharging and coagulating it or by air drying. The solidified material discharged into a flat shape from a slit nozzle can also be dried by continuously flowing it onto a smooth belt conveyor with a hydrophobic surface. The dried collagen film was subjected to crosslinking between collagen molecules using a conventional method. Crosslinking can be carried out by treatment with an aqueous crosslinking agent solution as shown in Table 1 or by irradiation with ultraviolet light. The crosslinking agent aqueous solution is an aqueous solution of aldehydes.

Approximately 0 when the aldehyde used is formaldehyde
．． It is an aqueous solution with a pH of 8 to 10 containing 0.05 to 2.0q6 formaldehyde and coexisting with a neutral salt, and when using glutaraldehyde, the aldehyde is 0.0
It is an aqueous solution with a pH of 4 to 6 containing 01 to 0.1% and coexisting with a neutral salt. In either case, the crosslinking treatment is carried out at about 30° C. for 2 to 20 hours. The amount of aldehyde bound to the collagen film after drying is 0.2 to 2.0% by weight for formaldehyde and 0.2% by weight for glutaraldehyde.
It is 2 to 5% by weight.

The UV lamp may be a conventional one; for example, in the example in Table 1, a 30W UV lamp made by Sankyo Denki is sharp and strong against a wavelength of 2537λ, and is 31
A lamp with a weak emission maximum at 30λ and a very weak emission maximum at 2965λ was used.

After introducing crosslinking, the water-washed membrane was placed in a hot air dryer for 15 minutes.
Dry for an hour. The dried collagen film is cut to a certain size, a number of small holes are made as necessary, and after sterilization, it is stored in disinfectant alcohol. Next, a detailed explanation will be given using examples. However, the examples are intended to explain the method of the present invention in detail, and are not intended to limit the scope. Example 1 A mixture of 20 parts of collagen solution (manufactured by the method described in Japanese Patent Publication No. 46-15033) and 80 parts of collagen fiber dispersion was used as a stock solution, and the concentration was 3.
%, PH3. The mixture was discharged into a 23% saline solution at 20° C. into a tubular shape at a speed of 8 m/min from a nozzle with an annular gap of 0.8 nm and a diameter of 18 nm to obtain a collagen film.

Air was blown into the tubular body to inflate the membrane, and one 30 W ultraviolet germicidal lamp was placed above and below the membrane, and the tubular body was rotated to introduce crosslinking under the UV-1 conditions shown in Table 1 above. The thickness of the collagen film was 0.05n. Cut this into a size of 5 x 5 cnL, diameter 0.11
41 holes were made in the sample, placed in a jacketed pressure chamber, sterilized in a force box 20 (ethylene oxide, carbon dioxide, 20:80) atmosphere at 40°C and 2 atm for 5 hours, and then stored in rubbing alcohol. did. Example 2 A mixture of 50 parts of a collagen solution (manufactured by the method described in Japanese Patent Publication No. 37-14426) and 50 parts of a collagen fiber dispersion was used as a stock solution, and the concentration was 5% and the pH was 3. The mixture was discharged into a 23% saline solution at a rate of 8 m/min through a slit nozzle with a slit of 0.8 mm and a width of 55 nm under O, and solidified.

Crosslinking was introduced into this according to the recipe shown in Table 1 F-2, and 50×
It was cut into a size of 50 nm and sterilized in the same manner as in Example 1 without making holes. The thickness of collagen film is 0.08
nu, and the amount of formaldehyde bound was 1.5%. Example 3 The collagen solution used in Example 2 was used alone to prepare a stock solution with a concentration of 5% and a pH of 3. Slit 0.8n) Width 55
It was discharged into a 23% saline solution from a slit nozzle at a speed of 8 m/min and solidified.

Crosslinking was introduced into this by the treatment shown in Table 1 G-1. After drying,
Cut into a size of 50 x 50n and make 4 holes of 0.15nφ.
One piece was opened and sterilized in the same manner as in Example 1. The amount of glutaraldehyde bound was 0.9%. Example 4 Special Public Service 1977-
The collagen solution obtained by the method described in Publication No. 15033 was used alone as a stock solution, and the concentration was 0.5% PH3. A collagen film was obtained by air-drying at O.

The thickness was 0.11 mm. This was cut into a size of 50 x 501 mm, and 25 holes with a diameter of 1.5 mm were drilled. F-1 in Table 1 was used for the crosslinking reaction. The amount of formaldehyde bound was 0.6%. After drying, the collagen film was placed in a jacketed pressure chamber and placed in a force box 20.
It was sterilized in (ethylene oxide/carbon dioxide 20:80) at 40° C. and 2 atm for 5 hours, and then stored in rubbing alcohol. Film-type collagen artificial skin was prepared using the above method and various biological experiments were conducted, and the products obtained by each method achieved sufficient therapeutic effects without much difference.

Among these, the results of clinical tests will be described as reference examples, particularly regarding the collagen films produced in Examples 1 and 2. Reference Example 1: A 6-month-old boy had severe burns on the back of his hand. The epidermis was completely necrotic and was peeling up, but the collagen film produced in Example 1 was applied directly and sterile gauze was placed on top. I fixed it with a bandage.

The gauze was changed every day, and the progress of healing of the wound was observed, and the progress was very good. On the 15th day, epithelialization occurred without any scars. Reference Example 2 A 4-year-old boy had a degree of forearm burn. When the collagen film produced in Example 2 was applied in the same manner as Reference Example 1, the wound area dried and epithelium was formed on the 6th day. and 1
On the 7th day, the wound was completely healed without any scars.

Observation results and discussion As mentioned above, the characteristics of the film-type artificial skin made of collagen are that it does not irritate the wound surface, drains the exudate from the wound surface, protects the wound surface from bacterial infection and stimulation by foreign substances, and especially prevents abnormal foreign body reactions. No inflammatory reactions are observed, and because it is made from a biological material called collagen, it is compatible with the body and generally heals more quickly than conventionally used materials.

Claims (1)

[Claims] 1. Consisting of an aqueous dispersion of collagen fibers and an aqueous collagen solution, the proportion of collagen contained in both is 80-
0:20-100 (dry weight ratio) of 0.2-6% raw material is extruded into a concentrated inorganic salt aqueous solution in a tubular or flat shape and coagulated, or a film is made by an air drying method, and then aldehydes are used. A method for producing a film-type collagen artificial skin characterized by crosslinking. 2 Consisting of an aqueous dispersion of collagen fibers and an aqueous collagen solution, the proportion of collagen contained in both is 80-
A 0:20-100 (dry weight ratio) stock solution of 0.2-6% is extruded into a concentrated inorganic salt aqueous solution in a tubular or planar shape and coagulated, or a film is made by an air-drying method, and then ultraviolet rays are irradiated. A method for producing a film-type collagen artificial skin characterized by crosslinking.